61907731 has 4 divisors (see below), whose sum is σ = 62031312. Its totient is φ = 61784152.

The previous prime is 61907717. The next prime is 61907759. The reversal of 61907731 is 13770916.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61907731 - 2⁷ = 61907603 is a prime.

It is a super-2 number, since 2×61907731² = 7665134315136722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61907701) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61036 + ... + 62041.

It is an arithmetic number, because the mean of its divisors is an integer number (15507828).

Almost surely, 2^61907731 is an apocalyptic number.

61907731 is a deficient number, since it is larger than the sum of its proper divisors (123581).

61907731 is a wasteful number, since it uses less digits than its factorization.

61907731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123580.

The product of its (nonzero) digits is 7938, while the sum is 34.

The square root of 61907731 is about 7868.1466051415. The cubic root of 61907731 is about 395.5927244030.

The spelling of 61907731 in words is "sixty-one million, nine hundred seven thousand, seven hundred thirty-one".